某大型地下硐室群稳定性分析及加固技术研究

Study on the Stability analysis and Reinforcement Technique of a Large Underground Chamber Group

某大型地下硐室群作为历史文物存续时间一般有数百年甚至千年,其安全等级不同于一般岩体工程,在各种因素影响下,大型硐室群岩体结构稳定性减弱,强度降低,最终导致岩体失稳、损坏,因此对其进行岩体稳定性分析和加固十分必要。该大型地下硐室群建设工程属于大型地下岩体开挖工程,岩体工程开挖前,通过工程地质调查显示,硐室群岩体整体稳定性较好,通过稳定性经验评价法对其进行了稳定性分析,发现硐室群整体稳定性好。在此基础上,采用三维数值仿真模拟计算方法对硐室群整体稳定性进行了评价,计算结果与工程地质调查、稳定性经验评价法的判断结果基本吻合,大型硐室群开挖后围岩总体上处于稳定状态。针对硐室内局部有断层破碎带和局部块体存在失稳隐患,提出了以"锚杆与注浆、浇筑混凝土相结合"的锚网喷为主的加固方案,有有效确保了其安全稳定。

A large underground cavern group as historical relics generally lasts for hundreds of years or even thousands of years,which level of security is different from general rock mass engineering,under the influence of various factors,large cavern group of rock mass structural stability and strength are reduced,eventually lead to the instability of rock mass,damage,therefore,it is necessary to conduct stability analysis of rock mass and reinforce technique study of the large underground chamber group.The large underground chamber group construction project belongs to the large underground rock mass excavation project.Before the excavation of the rock mass project,the engineering geological survey results show that the overall stability of the rock mass of the chamber group isgood,and the stability analysis is carried out by the stability empirical evaluation method,it is found that the overall stability of the chamber group is good.Based on the above discussion results,the three-dimensional numerical simulation method is used to evaluate the overall stability of the chamber group.The calculation results are basically consistent with those of the engineering geological survey and the stability empirical evaluation method.The surrounding rock of the large chamber group after excavation is generally in a stable state.In view of the local fault fracture zone and the instability hidden danger of the local block in the adit,the reinforcement scheme of anchor net spraying,which is based on the combination of anchor bolt,grouting and pouring concrete is proposed,it is help for effectively ensuring its safety and stability.